Switches > Solid State Switches > UE One Series


United Electric (UE) One Series Hybrid Pressure and Temperature Transmitter-Switches

The latest release of United Electric's One Series provides explosion-, flame-proof, intrinsically safe, and non-incendive devices to monitor gauge pressure, differential pressure, or temperature for critical alarm and shutdown applications in harsh, hazardous environments. With a digital process display and available 4-20 mA output, the One Series can provide the functions of a switch, a gauge, and a transmitter with only one connection to the process.

UE One Series is available in two-wire analog loop powered, two-wire discrete input powered, and externally powered models, and as switch-only, transmitter-only, or transmitter/switch versions. Transmitter and hybrid transmitter-switch One Series now feature HART® communications so you can program or troubleshoot without removing the enclosure cover to maintain device integrity, even in explosive environments.

Key Specifications

  • Switch only, transmitter only, or hybrid transmitter/switch models available
  • Two new switch-only models now available: High voltage, low current for compatibility to worldwide DCS and PLC systems, and high voltage, hig current for switching high level loads directly at the measurement point
  • NAMUR standard and HART® enabled transmitter; 4-20 mA output plus programmable switch for process monitoring, alarm, and shutdown
  • Switch-only models replace mechanical switches for cost-effective upgrades using existing wiring
  • Adjustable Ranges: Pressure -14.7 to 6000 PSI, Temperature -40° to 1000°F, Differential Pressure 0 to 200 PSID
  • Configurable "I Am Working" self-diagnostics ensure the instrument is functioning properly
  • Display and keypad provide easy, fast, secure field programming without taking the device out of service
  • Programmable setpoint and deadband provide versatile, accurate, repeatable alarm and shutdown switching
  • All models UL, CSA approved for Class I Div 1, Class II Div 1, Class III, plus Class 2 Zone 1, and Class 1 Zone 2 environments
  • Need a transmitter/switch for functional safety applications?
    See the UE One Series Safety Transmitter

Model Selection Guide

Use this table to find the right model for your application.  Don't see the option you need? Call a Lesman sales specialist at 800-953-7626

Make one selection from each table section below, using the availability column as your guide. See notes below for any restrictions or comments.
A finished catalog number looks like this: 2W2D00-P-10/M276

Description Catalog
One Series digital indicating MOSFET switch, two wire, discrete input power
Dust-Ignition proof, 12-30 VDC, 40 mA switch
Explosion/Flameproof, 12-30 VDC, 40 mA switch
Dust-Ignition proof, 30-50 VDC, 40 mA switch
Explosion/Flameproof, 30-50 VDC, 40 mA switch
Dust-Ignition proof, 90-130 VAC/DC, 100 mA switch
Explosion/Flameproof, 90-130 VAC/DC, 100 mA switch



One Series digital solid state relay switch, two wire, loop power, with 4-20 mA output
Dust-Ignition proof, 0-140 VAC/DC, 0.6A SSR
Explosion/Flameproof, 0-140 VAC/DC, 0.6A SSR
Dust-Ignition proof, 0-280 VAC/DC, 0.3A SSR
Explosion/Flameproof, 0-280 VAC/DC, 0.3A SSR

One Series digital solid state relay switch, four wire, external power
Dust-Ignition proof, 90-130 FAC, 24-280 VAC, 10A SSR
Explosion/Flameproof, 90-130 VAC, 24-280 VAC, 10A SSR

One Series digital indicatin, external power, 10-30 VDC, dual solid state relay switch, with 4-20 mA output
Dust-Ignition proof, Two 75-250 VAC 1.5A SSRs
Explosion/Flameproof, Two 75-250 VAC 1.5A SSRs
Dust-Ignition proof, Two 0-140 VAC/VDC 0.6A SSRs
Explosion/Flameproof, Two 0-140 VAC/VDC 0.6A SSRs
Dust-Ignition proof, One 75-250 VAC 1.5A SSR,
 One 0-140 VAC/VDC 0.6A SSR
Explosion/Flameproof, One 75-250 VAC 1.5A SSR,
 One 0-140 VAC/VDC 0.6A SSR






Sensor Type and Range Selection
Pressure Sensor, 1/2" NPTF
Differential Pressure Sensor, 1/4" NPTM
Temperature Sensor, 100Ω RTD, 304SS Sheath


Range Max. Overrange  
-14.7 to 30 PSI
-14.7 to 100 PSI
0-5 PSI
0-15 PSI
0-30 PSI
0-50 PSI
0-100 PSI
0-300 PSI
0-500 PSI
0-1000 PSI
0-3000 PSI
0-4500 PSI
0-6000 PSI
60 PSI
200 PSI
10 PSI
30 PSI
60 PSI
100 PSI
200 PSI
600 PSI
1000 PSI
2000 PSI
6000 PSI
9000 PSI
12000 PSI

0-5 PSID
0-50 PSID
0-100 PSID
0-200 PSID
100 PSID
200 PSID
400 PSID

Temperature Range and Configuration
Local Sensor -50° to 450°F, 4" probe length
-50° to 450°F, 6" probe length
-50° to 450°F, 10" probe length

Remote Sensor -300° to 200°F, 2.5" probe length, 6' MI cable
-50° to 450°F, 6" probe length, 6' Teflon® cable
-50° to 1000°F, 2.5" probe length, 6' MI cable

Remote Sensor
Custom Cable Length
-300° to 200°F, 2.5" probe length, up to 30' MI extension cable
-50° to 450°F 6" probe length, up to 30' Teflon® extension cable
-50° to 1000°F, 2.5" probe length, up to 30' MI extension cable
Factory set parameters
Display units in Bar or mBar
Paper tag
1/2" NPTM compression fitting (for TL and TR sensors)






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